Laser beam scanning apparatus for controlling diameter of light spot
US5557449A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1994 |
| Grant date | Sep 17, 1996 |
| Priority date | — |
| Expiry date | Apr 26, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/1135
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A laser beam scanning apparatus includes: a light source unit for emitting a collimated laser light beam; a rotary deflector unit for deflecting a laser light beam from the light source unit; a focusing unit for converting the deflected light beam into a convergent light beam, and for focusing the convergent light beam on a recording medium as a light spot, so that the focused light beam scans the recording medium in a main scanning direction when the rotary deflector unit is rotated; and a beam shape control unit for changing the sectional shape of a laser light beam emitted by the light source unit to a first sectional shape by restricting the laser light beam by using an opening of the beam shape control unit, the opening of the beam shape control unit having a predetermined sectional shape and dimensions, so that a diameter of the light spot on the recording medium is changed to a desired diameter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.